The disclosures herein relate generally to combines and more particularly to the grain unloading apparatus of a combine.
Agriculture equipment such as a combine or agricultural vehicle utilizes a head or other implement to perform various operations on a field. Combines often employ an implement such as a harvester or header attached to a feeder to harvest a crop or other plant-related matter. The feeder receives the cut or harvested crop from the header and provides the harvested crop to various pieces of equipment within the combine which perform assorted operations on the harvested crop such as sorting, separating, spreading, storing, or other agricultural functions.
Generally, combines have a combustion engine or mechanical power source indirectly driving the various pieces of equipment which operate on the harvested crop. The various pieces of equipment can include, but are not limited to, a feeder which receives the harvested crop from the header and transports the harvested crop to within the combine, a rotor which receives the harvested crop from the feeder and spins axially to thresh or separate the seed from the non-seed material of the harvested crop, a shoe shaker which separates additional seed from the non-seed material from the rotor, a straw spreader which spins to throw the non-seed material received from the shoe shaker out of the combine, a tailings elevator which conveys seed from the shoe shaker to the rotor, a clean grain elevator which transports seed from the rotor to the grain storage tank or external grain storage area, a discharge beater, a chopper which cuts the non-seed material for spreading by the straw spreader, a cleaning fan which provides cross air movement across the seed material to clean the seed material as it is conveyed through the combine, and a rotary air screen fan which provides cooling for the combustion engine, as well as other types of devices which are driven by the engine.
An unloader apparatus, typically a swingable auger tube, is conventionally stowed alongside the combine in a plane parallel with the combine's wheels. This unloader tube is capable of swinging from the stowed position to a position which is approximately 90 degrees perpendicular to the stowed position. The unloader tube is swung back and forth by the operator over a grain receiving bin in a storage vehicle which is positioned alongside the combine to permit the bin to be “topped off”. If the unloader tube were not swingable, the distribution of grain would peak at some areas of the bin and be low in other areas of the bin resulting in the bin not being filled to capacity.
One conventional control mechanism for swinging the unloader tube in and out over the grain receiving bin includes a latching extend switch and a latching retract switch. In this approach, the operator moves the extend switch to a mechanically latched position which causes the unloader tube to swing outwardly. To halt this outward swinging motion, the operator returns the unloader extend switch to the unlatched position. To retract the unloader tube, the operator moves the retract switch to a mechanically latched position which causes the tube to reverse direction and start to move inwardly back toward the stowed position. The tube's inward swinging motion continues until either the retract switch is unlatched by the operator or the tube reaches the stowed position.
In addition to simply swinging the tube in and out from a stowed position to a work position and vice versa, the extend and retract switches are used by the operator to swing the tube back and forth over the grain receiving bin of the storage vehicle to more evenly distribute grain within the bin. In other words, this latching switch mechanism is used to “top off” the bin. While the latching switch mechanism does perform the described function of moving the tube inward and outward, as a practical matter it can be difficult to use this mechanism to effectively “top off” the bin. The problem with such latching systems is that at critical times (i.e., when an operator is trying to “top off” a transportation or storage device) not enough control is available to the operator.
What is needed is an unloading apparatus and method which provides the operator with greater control over the position of the unloading apparatus.